Change 478724 had a related patch set uploaded (by Jforrester; owner: Jforrester):
[operations/mediawiki-config@master] Disable ParserMigration now that Raggett has been dropped from MW, Part I

https://gerrit.wikimedia.org/r/478724

Oops, should have remembered this; my fault, sorry.

Change 478724 merged by jenkins-bot:
[operations/mediawiki-config@master] Disable ParserMigration now that Raggett has been dropped from MW, Part I

https://gerrit.wikimedia.org/r/478724

Mentioned in SAL (#wikimedia-operations) [2018-12-10T17:29:39Z] <jforrester@deploy1001> Synchronized wmf-config/CommonSettings.php: T211527 Hot-deploy Disable ParserMigration now that Raggett has been dropped (duration: 00m 47s)

In T211527#4811253, @Jdforrester-WMF wrote:

So this is now fixed by emergency-disabling the extension. I've written the patches to de-deploy it, but I'll wait for sign-off from the team that this was an intended consequence of their work. https://gerrit.wikimedia.org/r/c/operations/mediawiki-config/+/478726/

We anticipated that ParserMigration will have to be disabled at some point and I had specifically asked on enwiki about this ( https://en.wikipedia.org/wiki/Wikipedia_talk:Linter#Question_about_ParserMigration_extension ). I think we can disable that extension for now.

ParserMigration is meant to be a generic tool and was used for the Tidy migration project right now and we anticipate it will be useful for other such projects in the future. Does it need to be de-deployed or is it sufficient to have it be disabled via the config?

In T211527#4811812, @ssastry wrote:

We anticipated that ParserMigration will have to be disabled at some point and I had specifically asked on enwiki about this ( https://en.wikipedia.org/wiki/Wikipedia_talk:Linter#Question_about_ParserMigration_extension ). I think we can disable that extension for now.

Excellent.

ParserMigration is meant to be a generic tool and was used for the Tidy migration project right now and we anticipate it will be useful for other such projects in the future. Does it need to be de-deployed or is it sufficient to have it be disabled via the config?

Nothing will break, but it's a mess. Re-deploying it later when we have a need won't be hard.

In T211527#4811816, @Jdforrester-WMF wrote:

In T211527#4811812, @ssastry wrote:

We anticipated that ParserMigration will have to be disabled at some point and I had specifically asked on enwiki about this ( https://en.wikipedia.org/wiki/Wikipedia_talk:Linter#Question_about_ParserMigration_extension ). I think we can disable that extension for now.

Excellent.

ParserMigration is meant to be a generic tool and was used for the Tidy migration project right now and we anticipate it will be useful for other such projects in the future. Does it need to be de-deployed or is it sufficient to have it be disabled via the config?

Nothing will break, but it's a mess. Re-deploying it later when we have a need won't be hard.

Works for me.

Now de-deployed.

Thanks, all. Step by step...